A freewheel sprocket as small as possible

[ferias77]

Hi,

I have a problem with my single speed friction drive folding bike : With the motor I can reach 42 km/h. But I can pedal only up to 20 km/h, otherwise I have to pedal too fast. I would like to pedal at 35 km/h to help the motor, as it was the case with my previous e-bike.
At the moment, I have 44 tooth on the chainset and 18 tooth on the freewheel sprocket. I would like to find the freewheel sprocket as small as possible. The ideal would be 10 or 11 tooth. With 10 tooth, I would pedal to 84 rpm for 35 km/h, it would be perfect (instead of 152 rpm at the moment, impossible... ). Apparently the minimum number of tooth to mount on a standard hub is 16... There are freewheels with less tooth, but it won't be possible to adapt...
http://www.customriders.com/prodshow.asp?prodid=9191&cat=17&parent=1001&sid=3

I have seen this post from recumpence, but I think it won't be possible on my bike : I don't have enough space for the adaptor.
http://endless-sphere.com/forums/viewtopic.php?f=28&t=22483&start=0

Is there any solution? If not, I could use a chainset with more tooth, but I would have prefered reducing the number of tooth of the freewheel sprocket.

Eric

 

[rodgah]

-change your rear hub over to a micro freewheel one.....they are available in 135mm and 100mm widths
-up your front chainring tooths
-dont bother pedalling

to be honest you will probably have to do both to comfortably pedal at 40km/h....unless you're an athlete.

Cheers

 

[mud2005]

the smallest freewheel sprocket I've seen is 9 tooth http://profileracing.com/profileracing/estore/product.php?productId=158&categoryId=8

but you gotta spend >$200

 

[ferias77]

Thanks for this information !

I found a hub with 10 teeth and a freewheel to chainreactioncycle for 57€ :
http://www.chainreactioncycles.com/Models.aspx?ModelID=16489
It could allow me not to change the front chainring tooth.I think I will do that.

And I will pedal only if the trip is long and I have not enough with my batteries :wink:

Eric

 

[Gordo]

Thanks for this information !

I found a hub with 10 teeth and a freewheel to chainreactioncycle for 57€ :
http://www.chainreactioncycles.com/Models.aspx?ModelID=16489
It could allow me not to change the front chainring tooth.I think I will do that.

And I will pedal only if the trip is long and I have not enough with my batteries :wink:

Eric

My 14 tooth cost $10 and a 10 tooth was available for the same. Try ebike.ca they have the 14 in stock.

 

[ferias77]

My 14 tooth cost $10 and a 10 tooth was available for the same. Try ebike.ca they have the 14 in stock.

Thanks for the information ! But I don't find any freewheel on the ebike.ca website, do you have a link?
Is the 14 tooth compatible with a standard mount?

 

[FFR Trikes]

Ferias,

13t is a nice compromise between minimal noise, affordablity, and chain life. I'm not sure if it'll work with your setup, but we have stainless micro freewheel adapters and 13t Odyssey freewheels in stock here in North Carolina.

Link to the store: http://www.ffrtrikes.com/parts

Thanks,
Tommy

 

[ferias77]

Thanks for the link ! Just to be sure to understand : the adapter permits to mount a microfreewheel on a 1/2 " shaft with a pressure screw, isn't it? Is it enough to transmit the power?
I think I could mount it if I lightly modify my hub.

Eric

 

[recumpence]

Yes, that is correct. There are two 1/4-20 set screws at 90 degrees around the hub of the FW adaptor. I run these on a couple of my bikes. They work well.

Matt

 

[mud2005]

Thanks for the link ! Just to be sure to understand : the adapter permits to mount a microfreewheel on a 1/2 " shaft with a pressure screw, isn't it? Is it enough to transmit the power?
I think I could mount it if I lightly modify my hub.

Eric

now I'm confused :? I thought you were looking for a freewheel for your rear wheel so you could pedal at higher speeds.

how is an adapter for a 1/2" shaft going to help you??

 

[Hillhater]

Yes, confused me too !
If you want to pedal at higher speeds, (and lower one too) then the simplest solution would be the Schlumpf Speed drive.
http://sheldonbrown.com/harris/schlumpf.html

kinda' spendy tho' !

 

[neptronix]

If we're talking about regular bicycle parts, there are a few freewheels available that have 11t teeth on them.
DNP & oldschool shimano megarange are what you need to look for.

The smallest single speed freewheel you're going to find for an english thread ( what all the hub motors come with ) is going to be 15t however.

11t + a 50t gear on my 26" wheels makes for pedaling up to ~35mph for me.

 

[Kin]

It's a folding bike, so it's probably 20". That's going to be about 25% less = only 26.6mph.


I've only contemplated every so often making a very big front chainring. Seems a lot harder to deal with the back because I'd have to change shifter, and then I dont know how to deal with the rest of my rings (at least on my 20" bike the rear is where all the gears are, and the front has just one ring).

At least for now I dont have my ebike put together, so I'm not worrying about it.

 

[Hillhater]

It's a folding bike, so it's probably 20". That's going to be about 25% less = only 26.6mph.

which would be just right for the 35-42kph that he wanted !

 

[Kin]

It's a folding bike, so it's probably 20". That's going to be about 25% less = only 26.6mph.

which would be just right for the 35-42kph that he wanted !

Very true- uhmm. Not sure what my point was, then. (sorry)

 

[ferias77]

Thanks for all this information !

In clearer, I would like pedalling at 70 rpm with my 20" folding bike at 40 km/h ( http://www.endless-sphere.com/forums/viewtopic.php?f=28&t=31457&start=15 ). So I need the freewheel compatible with standard english thread with the less teeth as possible. I thought I could modify my hub and the 1/2" shaft adapter to make it compatible.

I didn't know the Schlumpf Speed drive, that's great !!! (except the price :wink: ). If I don't find any cheaper solution, I will do it !
Indeed, using a cassette with a small sprocket with 11 tooth would be a good solution ! The oldschool shimano megarange is compatible with a standard english thread? I will see if I can find it and if it is compatible with my bike.

 

[spinningmagnets]

I apologize if I misunderstand your question (friction drive on a single-speed wheel?), but...There are integrated freewheel/hubs for BMX that can be laced to your rims. The smallest tooth-count I found is a "Stolen Roulette" $110 hub with 8T (larger tooth-counts available) which has 36-hole flanges for the spokes. there are many other similar choices, this is just what I stumbled across quickly.
http://www.jensonusa.com/store/product/HU276D00-Stolen+Roulette+Cassette+Hub.aspx

 

[Hillhater]

Well, if you are going to the extent of changing the hub, you may as well fit one of the IG multi speed hubs ( S Archer, Sram, Shimano, etc) that will give you the benefit of pedal assist at both high and low speed.
A 3 speeder should be enough.
I would hate to be stuck with a single speed 11T gear on a bike with no power assist...and at hill starts.

 

[mud2005]

So I need the freewheel compatible with standard english thread with the less teeth as possible

smallest available single speed freewheel for english thread is 16T

The oldschool shimano megarange is compatible with a standard english thread? I will see if I can find it and if it is compatible with my bike.

yes it's compatible w/ english thread. no, you won't find one. last one I saw was on ebay selling for over $100. check out ebies.ca for a cheap version of the shimano http://www.ebikes.ca/store/store_motors.php

does your bike have a hanger for a rear deraileur? w/o it you may have trouble going from SS to a cassette

the mentioned swapping of your hub to a internally geared one may be your best solution

 

[Miles]

So I need the freewheel compatible with standard english thread with the less teeth as possible

smallest available single speed freewheel for english thread is 16T

Some places still have stock of the AC Racing 15t. Buy one while you can..... http://americancycle.com/product/ac-race-888-freewheel-1984.htm

 

[ferias77]

Thanks for the information !

Well, if you are going to the extent of changing the hub, you may as well fit one of the IG multi speed hubs ( S Archer, Sram, Shimano, etc) that will give you the benefit of pedal assist at both high and low speed.
A 3 speeder should be enough.
I would hate to be stuck with a single speed 11T gear on a bike with no power assist...and at hill starts.

I had speeds on my previous e-bike and I have them never used. So I choose a single speed bike to be as simple as possible.

So either I mount the AC racing 15T (but I don't find the amount for shipping on americancycle...) and change the chainring for a bigger, or change the hub of the back wheel for a model with an integrated freewheel.

Eric